When a skipper is prepared to be a stand-in, you know something special is happening.

2013 has been a difficult year for Vermaelen. His form has floundered and he has found himself used predominantly as a substitute, arriving late on in matches to shore up victories with a few timely clearances.

In his absence, Per Mertesacker and Laurent Koscielny have formed an effective partnership. Vermaelen's personal nadir came during last season's derby defeat at Tottenham when Arsenal's offside trap was pierced all too easily by Spurs. Since then, in the Belgian's absence, Arsenal have been a model of efficiency and organisation.

When Mertesacker was ruled out of Sunday's match with Manchester United, Arsenal fans mourned the loss of their first-choice partnership.

Vermaelen was called into action at Old Trafford at late notice and there were understandable concerns that he might be off the pace. This was to be Vermaelen's first start of the season, at the most intimidating away ground in the Premier League.

What's more, this was at a venue on which he made a costly mistake last season, skewing a clearance into the path of Robin van Persie to gift United the lead and exacerbate the erosion of his own reputation.

Arsenal fans' fears were misplaced.

Vermaelen put in a bullish display to remind Arsenal fans, and the watching ArseneWenger, of his ability.

The stats demonstrate how effective Vermaelen was. He was particularly good in the air. According to Squawka, Vermaelen won four out of his five headed duels. When van Persie rose to head home the winning goal, Vermaelen was not culpable: He was diligently marking in a different zone.

The Belgian international also won 100 percent of his tackles and made four interceptions—the highest tally on the Arsenal team.

He also made a staggering 11 clearances. No player on either side cleared their lines as frequently as Vermaelen.

However, his performance won't be enough to earn him an immediate reprieve. When Mertesacker returns to fitness, he will almost certainly be restored alongside Koscielny in the middle of the defence.

Many players of Vermaelen's stature would refuse to accept such a situation. In a World Cup year, less committed players would surely agitate for a January departure.

Not Vermaelen. He is a competitor in every sense. He's prepared to compete for a place in the squad if it helps Arsenal compete for honours.

Some might suggest that a substitute is not worthy of the captaincy. However, Vermaelen is demonstrating the selflessness required of great leaders. He rarely gets an opportunity to lead by example on the pitch but is perennially doing so off it.

Vermaelen's attitude is indicative of the new focus that binds Arsenal. The team spirit in this current side is enormous. Players work tirelessly off the ball to ensure the Gunners get the results they need. Strikers track back, and substitutes wait patiently for their chance to impress.

If Arsenal are to achieve their ambitions this season, that spirit will be vital.

As for Vermaelen, he will know that Sunday's performance has stood him in good stead. The next time Mertesacker or Koscielny is absent, fans will not be worried. In a long season, one of the few guarantees is that Arsenal will pick up injuries and suspensions.